I disagree. They committed no sin nor were they nieve. To say either is to blame the victims for being raped.
They signed up and paid very good money for a cruise/vacation. Vacations are to rest your worries, especially cruises. The assumption that all stops are vetted to be safe, else the ship wouldn’t go to that location.
They went to a part of the world where harm to a Western person is nearly certain and they weren’t being naive?
They were attractive women, with no male escorts and no other means of protection and they drank from a drink that was prepared onsite and wasn’t sealed by a corporation and they expected everything to be fine.
That’s being naive and they paid for it.
The rest of the world is nothing like suburban America. If you are traveling internationally, you cannot expect safety.